Add support for TypeDefinition in OData V4

TypeDefinitions are simply aliases for primitive types. They can be
annotated. Thus, reimplementation of annotation for V4 is included in
this commit.

Children of ODataVersion have to specify which annotations are supported
and how they should be processed. Annotation are parsed using function
'build_annotation'. As annotation are always tied to specific element
and there is no centralized repository of annotations this function must
return void.

http://docs.oasis-open.org/odata/odata/v4.0/errata03/os/complete/part3-csdl/odata-v4.0-errata03-os-part3-csdl-complete.html#_Toc453752574

Author: mamiksik

CHANGELOG.md

@@ -14,6 +14,7 @@ and this project adheres to [Semantic Versioning](http://semver.org/).
 - Support for OData V4 primitive types - Martin Miksik
 - Support for navigation property in OData v4 - Martin Miksik
 - Support for EntitySet in OData v4 - Martin Miksik
+- Support for TypeDefinition in OData v4 - Martin Miksik
 
 ### Changed
 - Implementation and naming schema of `from_etree` - Martin Miksik

pyodata/config.py

@@ -7,7 +7,7 @@
 
 # pylint: disable=cyclic-import
 if TYPE_CHECKING:
-    from pyodata.model.elements import Typ  # noqa
+    from pyodata.model.elements import Typ, Annotation  # noqa
 
 
 class ODATAVersion(ABC):
@@ -32,6 +32,11 @@ def primitive_types() -> List['Typ']:
     def build_functions() -> Dict[type, Callable]:
         """ Here we define which elements are supported and what is their python representation"""
 
+    @staticmethod
+    @abstractmethod
+    def annotations() -> Dict['Annotation', Callable]:
+        """ Here we define which annotations are supported and what is their python representation"""
+
 
 class Config:
     # pylint: disable=too-many-instance-attributes,missing-docstring
@@ -73,8 +78,8 @@ def __init__(self,
         self._odata_version = odata_version
 
         self._sap_value_helper_directions = None
-        self._sap_annotation_value_list = None
         self._annotation_namespaces = None
+        self._aliases: Dict[str, str] = dict()
 
     def err_policy(self, error: ParserError) -> ErrorPolicy:
         """ Returns error policy for given error. If custom error policy fo error is set, then returns that."""
@@ -111,8 +116,12 @@ def sap_value_helper_directions(self):
         return self._sap_value_helper_directions
 
     @property
-    def sap_annotation_value_list(self):
-        return self._sap_annotation_value_list
+    def aliases(self) -> Dict[str, str]:
+        return self._aliases
+
+    @aliases.setter
+    def aliases(self, value: Dict[str, str]):
+        self._aliases = value
 
     @property
     def annotation_namespace(self):

pyodata/model/build_functions.py

@@ -4,14 +4,16 @@
 import copy
 import logging
 
+from pyodata.policies import ParserError
 from pyodata.config import Config
-from pyodata.exceptions import PyODataParserError
+from pyodata.exceptions import PyODataParserError, PyODataModelError
 from pyodata.model.elements import sap_attribute_get_bool, sap_attribute_get_string, StructType, StructTypeProperty, \
     Types, EntitySet, ValueHelper, ValueHelperParameter, FunctionImportParameter, \
-    FunctionImport, metadata_attribute_get, EntityType, ComplexType, Annotation, build_element
+    FunctionImport, metadata_attribute_get, EntityType, ComplexType, build_element
 
-from pyodata.v4 import ODataV4
-import pyodata.v4.elements as v4
+# pylint: disable=cyclic-import
+# When using `import xxx as yyy` it is not a problem and we need this dependency
+import pyodata.v4 as v4
 
 
 def modlog():
@@ -122,39 +124,15 @@ def build_entity_set(config, entity_set_node):
     req_filter = sap_attribute_get_bool(entity_set_node, 'requires-filter', False)
     label = sap_attribute_get_string(entity_set_node, 'label')
 
-    if config.odata_version == ODataV4:
-        return v4.EntitySet(name, et_info, addressable, creatable, updatable, deletable, searchable, countable, pageable,
-                         topable, req_filter, label, nav_prop_bins)
+    if config.odata_version == v4.ODataV4:
+        return v4.EntitySet(name, et_info, addressable, creatable, updatable, deletable, searchable, countable,
+                            pageable, topable, req_filter, label, nav_prop_bins)
 
     return EntitySet(name, et_info, addressable, creatable, updatable, deletable, searchable, countable, pageable,
                      topable, req_filter, label)
 
 
-def build_external_annotation(config, annotations_node):
-    target = annotations_node.get('Target')
-
-    if annotations_node.get('Qualifier'):
-        modlog().warning('Ignoring qualified Annotations of %s', target)
-        return
-
-    for annotation in annotations_node.xpath('edm:Annotation', namespaces=config.annotation_namespace):
-        annot = build_element(Annotation, config, target=target, annotation_node=annotation)
-        if annot is None:
-            continue
-        yield annot
-
-
-def build_annotation(config, target, annotation_node):
-    term = annotation_node.get('Term')
-
-    if term in config.sap_annotation_value_list:
-        return build_element(ValueHelper, config, target=target, annotation_node=annotation_node)
-
-    modlog().warning('Unsupported Annotation( %s )', term)
-    return None
-
-
-def build_value_helper(config, target, annotation_node):
+def build_value_helper(config, target, annotation_node, schema):
     label = None
     collection_path = None
     search_supported = False
@@ -179,7 +157,31 @@ def build_value_helper(config, target, annotation_node):
             param.value_helper = value_helper
             value_helper._parameters.append(param)
 
-    return value_helper
+    try:
+        try:
+            value_helper.entity_set = schema.entity_set(
+                value_helper.collection_path, namespace=value_helper.element_namespace)
+        except KeyError:
+            raise RuntimeError(f'Entity Set {value_helper.collection_path} '
+                               f'for {value_helper} does not exist')
+
+        try:
+            vh_type = schema.typ(value_helper.proprty_entity_type_name,
+                                 namespace=value_helper.element_namespace)
+        except KeyError:
+            raise RuntimeError(f'Target Type {value_helper.proprty_entity_type_name} '
+                               f'of {value_helper} does not exist')
+
+        try:
+            target_proprty = vh_type.proprty(value_helper.proprty_name)
+        except KeyError:
+            raise RuntimeError(f'Target Property {value_helper.proprty_name} '
+                               f'of {vh_type} as defined in {value_helper} does not exist')
+
+        value_helper.proprty = target_proprty
+        target_proprty.value_helper = value_helper
+    except (RuntimeError, PyODataModelError) as ex:
+        config.err_policy(ParserError.ANNOTATION).resolve(ex)
 
 
 def build_value_helper_parameter(config, value_help_parameter_node):

pyodata/model/builder.py

@@ -1,6 +1,5 @@
 """Metadata Builder Implementation"""
 
-import collections
 import io
 from lxml import etree
 
@@ -24,9 +23,6 @@
 }
 
 
-SAP_ANNOTATION_VALUE_LIST = ['com.sap.vocabularies.Common.v1.ValueList']
-
-
 # pylint: disable=protected-access
 class MetadataBuilder:
     """Metadata builder"""
@@ -99,7 +95,6 @@ def build(self):
         self._config.namespaces = namespaces
 
         self._config._sap_value_helper_directions = SAP_VALUE_HELPER_DIRECTIONS
-        self._config._sap_annotation_value_list = SAP_ANNOTATION_VALUE_LIST
         self._config._annotation_namespaces = ANNOTATION_NAMESPACES
 
         self.update_alias(self.get_aliases(xml, self._config), self._config)
@@ -111,31 +106,32 @@ def build(self):
     def get_aliases(edmx, config: Config):
         """Get all aliases"""
 
-        aliases = collections.defaultdict(set)
+        # aliases = collections.defaultdict(set)
+        aliases = {}
         edm_root = edmx.xpath('/edmx:Edmx', namespaces=config.namespaces)
         if edm_root:
             edm_ref_includes = edm_root[0].xpath('edmx:Reference/edmx:Include', namespaces=config.annotation_namespace)
             for ref_incl in edm_ref_includes:
                 namespace = ref_incl.get('Namespace')
                 alias = ref_incl.get('Alias')
                 if namespace is not None and alias is not None:
-                    aliases[namespace].add(alias)
+                    aliases[alias] = namespace
+                    # aliases[namespace].add(alias)
 
         return aliases
 
     @staticmethod
     def update_alias(aliases, config: Config):
         """Update config with aliases"""
-
-        namespace, suffix = config.sap_annotation_value_list[0].rsplit('.', 1)
-        config._sap_annotation_value_list.extend([alias + '.' + suffix for alias in aliases[namespace]])
-
+        config.aliases = aliases
         helper_direction_keys = list(config.sap_value_helper_directions.keys())
+
         for direction_key in helper_direction_keys:
             namespace, suffix = direction_key.rsplit('.', 1)
-            for alias in aliases[namespace]:
-                config._sap_value_helper_directions[alias + '.' + suffix] = \
-                    config.sap_value_helper_directions[direction_key]
+            for alias, alias_namespace in aliases.items():
+                if alias_namespace == namespace:
+                    config._sap_value_helper_directions[alias + '.' + suffix] = \
+                        config.sap_value_helper_directions[direction_key]
 
 
 def schema_from_xml(metadata_xml, namespaces=None):